We prospectively evaluated bronchial washings from 45 patients aged 1 month to 25 years (mean 3.3 years) for the presence of lipid-laden macrophages. By grading the amount of intracellular oil-red-O-positive material, we determined a semiquantitative lipid-laden macrophage index for each patient. All patients observed to be definite aspirators (n = 22) had indexes greater than or equal to 86 (mean +/- SD, 139 +/- 46). All patients with no clinical suspicion of aspiration (n = 23) had indexes less than or equal to 72 (mean +/- SD, 21 +/- 20). Our results suggest that simply sighting lipid-laden macrophages in a nonspecific finding, but quantitation of these cells may be a very good test for recurrent aspiration of food substances in children. This test appears to be more sensitive than radiographic studies.

High levels of lipid-laden macrophages (LLM) in bronchial washings have been associated with food aspiration. We studied the time course of appearance and clearance of LLM in rabbits undergoing either a single milk instillation, five weekly milk instillations or saline (control) instillations into the airways. Cells were obtained by bronchoalveolar lavage of intubated rabbits at uniform time intervals following the single or the last of five milk/saline instillations. LLM semi-quantitative indexes were derived using oil-red-O staining. Significantly elevated indexes were found in both milk groups 6 hr after milk instillation. In the single saline and milk instillation groups the indexes were not different beginning on the 4th day, and indexes from 8 of 9 rabbits had returned to baseline by the 6th day. However, indexes remained significantly elevated up to 17 days in the group receiving weekly milk instillations. Indexes from all rabbits in the repeat milk instillation group remained elevated for 12 days or longer. This group also developed increased numbers of binucleated macrophages. Quantitation of LLM in this model appears to be a sensitive indicator of recurrent lipid aspiration, these cells remaining in the airways for several days after the last aspiration event.

No abstract

No abstract

No abstract